Alert archive / Michigan / Mesoscale Discussions in 2011

Mesoscale Discussion 1649

July 18, 20117 counties in Michigan; Manitowoc County, Sheboygan County, Wisconsin

The Storm Prediction Center issued this mesoscale discussion at Jul 18, 2011, 10:54 AM EDT for 7 counties in Michigan; Manitowoc County, Sheboygan County, Wisconsin. It was in force for 96 min.

The area

The outline as issued.

The facts

Issued: Jul 18, 2011, 10:54 AM EDT (14:54 UTC)
Expired: Jul 18, 2011, 12:30 PM EDT
In force: 96 min
Issued by: the Storm Prediction Center

Counties Lake County, MI, Manistee County, MI, Mason County, MI, Mecosta County, MI, Muskegon County, MI, Newaygo County, MI, Oceana County, MI, Manitowoc County, WI, Sheboygan County, WI

The radar

The Green Bay radar (KGRB), 104 km from the middle of the area, began a volume at 14:57 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

The nearest sounding before it

Green Bay/Straub, WI (KGRB), launched 12:00Z, 2.9 hours before the alert went out and 102 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 3928 J/kg
Mixed-layer CIN: -31 J/kg
Mixed-layer LCL: 613 m above ground
0-6 km bulk shear: 47 kt
0-1 km storm-relative helicity: 106 m²/s²
0-3 km storm-relative helicity: 111 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 9.7

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

281 
ACUS11 KWNS 181454
SWOMCD
SPC MCD 181454 
MIZ000-WIZ000-181630-

MESOSCALE DISCUSSION 1649
NWS STORM PREDICTION CENTER NORMAN OK
0954 AM CDT MON JUL 18 2011

AREAS AFFECTED...LWR MI

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

VALID 181454Z - 181630Z

THE NEED FOR AN ADDITIONAL WW EAST OF WW 656 IS NOT ANTICIPATED IN
THE SHORT TERM...BUT TRENDS WILL CONTINUE TO BE MONITORED.

SHRINKING CLUSTER OF STORMS NOW PASSING TO THE SOUTH AND EAST OF
GREEN BAY HAS BEEN ACCOMPANIED BY A BELT OF STRONGER WINDS THAT HAVE
REACHED THE SURFACE WITH A NARROW SWATH OF WINDS AT LEAST
APPROACHING AND OCCASIONALLY EXCEEDING SEVERE LIMITS.  SURFACE
ANALYSIS INDICATES LITTLE IN THE WAY OF A SIGNIFICANT COLD POOL WITH
ACTIVITY...WITH THE VERY MOIST AND POTENTIALLY UNSTABLE DOWNSTREAM
BOUNDARY LAYER REMAINING STRONGLY CAPPED.  IT DOES APPEAR THAT A
ZONE OF ENHANCED LOWER/MID TROPOSPHERIC WARM ADVECTION COULD
MAINTAIN CONVECTIVE DEVELOPMENT ACROSS LAKE MICHIGAN INTO AREAS OF
LOWER MICHIGAN SOUTH/SOUTHEAST OF MANISTEE BETWEEN NOW AND 16-17Z. 
HOWEVER...THE THREAT FOR CONTINUING STRONG WIND GUSTS APPEARS TO BE
DIMINISHING.

..KERR.. 07/18/2011

...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...

ATTN...WFO...APX...GRR...GRB...MKX...

LAT...LON   44598777 44388666 44118561 43518511 43158594 43378722
            43758792 44098813 44368802 44598777

SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jul 17, 10:24 PM EDT	Mesoscale Discussion	SPC	Menominee	66 min
Jul 18, 12:06 AM EDT	Mesoscale Discussion	SPC	Antrim, Benzie, Charlevoix, Cheboygan, Crawford, Emmet and 13 more	54 min
Jul 18, 1:29 PM EDT	Mesoscale Discussion	SPC	Bay, Clare, Clinton, Eaton, Genesee, Gladwin and 18 more	91 min
Jul 17, 8:22 PM EDT	Severe Thunderstorm Watch	SPC	Brown, Calumet, Door, Florence, Forest, Kewaunee and 17 more	4 hr
Jul 18, 7:30 AM EDT	Mesoscale Discussion	SPC	Adams, Clark, Columbia, Crawford, Dane, Dodge and 25 more	2 hr
Jul 18, 9:05 AM EDT	Severe Thunderstorm Watch	SPC	Adams, Brown, Buffalo, Calumet, Clark, Columbia and 32 more	4 hr
Jul 18, 3:06 PM EDT	Mesoscale Discussion	SPC	Barron, Brown, Chippewa, Clark, Dunn, Eau Claire and 17 more	84 min
Jul 18, 3:26 PM EDT	Severe Thunderstorm Watch	SPC	Adams, Brown, Calumet, Chippewa, Clark, Door and 28 more	7 hr
Jul 18, 6:42 PM EDT	Mesoscale Discussion	SPC	Adams, Brown, Calumet, Chippewa, Clark, Eau Claire and 21 more	63 min
Jul 18, 7:18 PM EDT	Severe Thunderstorm Watch	SPC	Columbia, Dane, Dodge, Fond du Lac, Green, Green Lake and 14 more	3 hr

Nearby

Mesoscale Discussions in Michigan, 2011 Mesoscale Discussions in Wisconsin, 2011 Every mesoscale discussion in 2011

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.